This release marks a major milestone in the Yii framework development. It includes many new significant features to the already powerful Yii framework. We added a PHPUnit-based testing framework so that developers can more easily write unit tests and functional tests; We added a form builder so that commonly used HTML forms can be built in terms of objects and thus enhance their reusability; We added support for changing skins for widgets globally; We also modified the way of performing relational ActiveRecord queries so that they are more intuitive and easier to use.

Besides all these core feature enhancements, we also started a new project called zii, which represents a set of official extensions for yii. The zii project will be under heavy development from now on, and we will include it in each of the 1.1 releases.

Do not use this release for production use. This is still an early alpha release, and thus may be subject to changes in future releases without prior notice.

We do not recommend you upgrade from 1.0 to 1.1 if your existing Yii-powered websites already working very well. Upgrading may need quite a bit effort if your project contains a lot of AR models due to the backward-compatibility breaking changes introduced in 1.1.

Yes, 1.0 will be maintained till the end of 2010. During the time, only bug fixes will be checked into this branch. New features and changes will all go into 1.1 and future 1.2 to maintain strict BC for 1.0.x.